The invention relates to a method of controlling a torque transmission system, to a torque transmission system for carrying out the method of controlling, and to a method of monitoring torque transmission systems.
It is known from the vehicle industry that, when changing the transmission ratio of a gear between a driving machine and a gearbox unit, the required clutching processes can be assisted or automated by a control or regulating algorithm. This facilitates the servicing of the engine unit or gearbox, and the clutching operation can be carried out in an energy saving manner with careful treatment of the materials. Furthermore, the control of a torque transmission system which is mounted at the output side of an automatic gearbox can be helpful, for example, in undertaking or guaranteeing adjustment processes and protective functions in the case of, for example, cone pulley belt contact gearboxes.
WO 94/04852 discloses a method of controlling torque transmission systems in conjunction with an automatic gearbox. The torque transmission system comprises a load branching out with a torque converter which is mounted in parallel with a friction clutch. In accordance with this method, a driving torque transmitted by an engine unit is broken up into a hydraulic part which is to be transmitted by the converter and a mechanical part which is to be transmitted by the friction clutch, such as a lockup clutch. A central computer unit determines or calculates, in dependency upon the relevant operating condition of the system, the torque which is to be transmitted each time by the friction clutch. The remaining torque to be transmitted by the hydraulic torque converter constitutes the difference between the applied torque and the torque transmitted by the friction clutch and corresponds directly to a slip between the input and output parts of the torque transmission system.
Such method of controlling can be resorted to only in conjunction with an automatic gearbox and a lockup clutch. However, the acceptability of automatic gearboxes is only minimal in many fields of use. Furthermore, a lockup clutch of such kind is cost-intensive and bulky.